To find the percentage of light bulbs that last more than 2110 hours, we need to calculate the z-score for 2110 hours and then find the area to the right of that z-score.
The z-score is calculated as follows:
z = (X - μ) / σ
z = (2110 - 2000) / 70
z = 0.1571
Now, we look up the z-score in the standard normal distribution table or use a calculator to find the percentage corresponding to a z-score of 0.1571. This percentage represents the percentage of light bulbs that last more than 2110 hours.
Using a standard normal distribution table or calculator, we find that the percentage of light bulbs that last more than 2110 hours is approximately 44.0% to the nearest tenth.
The amount of time a certain brand of light bulb lasts is normally distributed with a mean of 2000 hours and a standard deviation of 70 hoursWhat percentage light bulbs last more than 2110 hours, to the nearest tenth?
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